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The mullite-zirconia composites were prepared by reaction-sintering of alumina and zircon powder. Besides, the slip casting method was employed for fabrication of these composites. Then, the effect of nano-TiO2 addition on the properties of these composites was investigated and the results were compared with micro-sized TiO2. Hence, the physical properties, phase composition, flexural strength and microstructure of these composites after firing at 1600°C were studied. The results showed that the flexural strength of composite tends to increase with the addition of 0.5 wt.% nano-TiO2. It is attributed to the formation of larger size rod-like ZrO2 and enhanced ceramic bonding between them

Carbon nanofibers (CNFs) have been synthesized in high yield (>70%) by catalytic chemical vapor deposition (CCVD) on Co/LiF catalyst using acetylene as carbon source. A novel catalyst support (LiF) is reported for the first time as an alternative for largescale production of carbon nanofibers while purification process of nanofibers is easier. In our experiment, the sealed furnace was heated at 700• C for 0.5 hour (the heating rate was 10 • C/min) and then cooled to room temperature in the furnace naturally. Catalytic chemical vapor deposition is of interest for fundamental understanding and improvement of commercial synthesis of carbon nanofibers (CNFs). The obtained sample was sequentially washed with ethanol, dilutes acid, and distilled water to remove residual impurities, amorphous carbon materials, and remaining of catalyst, and then dried at 110• C for 24 hours. The combined physical characterization through several techniques, such as high-resolution transmission electron microscope (TEM), scanning electron microscope (SEM), thermogarvimetric analysis (TGA), and zeta-sizer and Raman spectroscopy, allows determining the geometric characteristic and the microstructure of individual carbon nanofibers. Catalytic chemical vapor deposition is of interest for fundamental understanding and improvement of commercial synthesis of carbon nanofibers (CNFs). As a matter of fact, the method of CCVD guarantees the production of CNFs for different applications.

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